Automobile heater



Feb- 3- w. G. MITCHELL ETAL ,3 3

AUTOMOBILE HEATER FiledMalrch 10, 1959 4 Sheets-Sheet l M a e M m M warjizioia l fi uzifyrerz Feb. 9,1943. w. G. MITCHELL 'El' AL 2,310,453

AUTOMOBILE HEATER FiledMarch 1Q, 1959 4 Sheets-Sheet 2 Feb. 9, 1943. I'w MlTCHELL r I 2,310,453

' AUTOMOBILE HEATER Filed March 1 0, 1939 4 Sheets-Sheet 3 Feb; 9, 1943.W.'G.MlTCHELL E1;AL-. I 3 5 AUTOMOBILE HEATER Filed' March 10, 1959 4Sheets-Sheet 4 wa er 67191264651 Q'rrzold'ffizllifyren.

Patented Feb. 9, 1943 AUTOMOBILE HEATER Walter .G. Mitchell, Oak Park,and Arnold P.

Hultgren, Chicago, 111., assignors to Sears, Rocbuck and 00., Chicago,111., a corporation of New York Application March 10, 1939, Serial No.260,900

13 Claims.

Our invention relates to automobile heaters, and has to do moreparticularly with an improved heater which is designed for otheroptional uses, including the defrosting of a. windshield.

A particularobject of our invention is to provide a device which iscapable either of simultaneously or alternatively heating and/ordefrosting at the will of an operator.

Another object is to provide a device of the type referred to which willhave improved heating efficiency. 7,

Still another object is to provide such a device wherein a portion ofthe heat transmitted through the heat exchange elements will berecirculated therethrough before it is discharged from the heater.

Another object is to provide a device of the type referred to whereinthe shape of the air channel is so designed that the air discharged fromthe heater is concentrated rather than difiused, thus providing a highertemperature of air where it is especially desired.

Still another object is to provide means for controlling the temperatureof defroster air.

Still another object is to provide a device of the type referred towhich will be simple and inexpensive to construct, easy to adjust,eflicient in operation, and generally satisfactory for the purposesdesired.

Various other objects and advantages will suggest themselves to thoseskilled in the art, as the description proceeds.

Referring now to the drawings forming a part of this specification andillustrating a preferred embodiment of our invention:

Fig. 1 is a front perspective view of a heater embodying our invention;

Fig. 2 is a vertical axial sectional View of the same;

Figs. 3 and 4 are sectional views taken substantially along the lines3-3 and 44, respectively, of Fig. 2;

Fig. 5 is a front elevational view of the same;

Fig. 6 is a perspective view of an air control plate forming a part ofthe front of the heater casing;

Fig. 7 is a perspective view of an air control door forming anotherelement of the front of the heater casing;

Fig. 8 is a fragmentary sectional view taken substantially along theline 8-8 of Fig. 2; and

Figs. 9 and 10 are vertical axial sectional views of the front of theheater casing illustrating diagrammatically the air paths underdifferent conditions of control.

In the preferred embodiment illustrated, the

heater comprises a casing indicated generally'by the numeral H3, inwhich is mounted a heat exchange unit indicated generally by the numeralI2. Mounted rearwardly of the heat exchange element is an air propellingunit indicated generally by the numeral Hi.

The air propelling unit comprises a U-shaped bracket [6, from the legsof which are vertically extending ears IT, IT, to which is secured, asby screws or the like, a spider bracket 18 carrying a motor 20 and a fanunit, indicated generally by the numeral 22, keyed to the shaft 23 ofthe motor. The fan unit comprises a squirrel cage type of centrifugalblower 25, the perforated rear wall 26 of which is secured to the motorshaft 23. The front edge of the squirrel cage has outwardly extendingears 2'! to which are secured as by rivets a plurality of blades 30which are preferably integral with an annular ring 3| which seatsagainst the front edge of the squirrel cage. The blades 30 are soarranged as to propel a current of air forwardly through the heatingunit. a

A circular blower housing 33 is disposed around the squirrel cage, saidhousing being'secured as by screws or the like to the bracket I8. Anoutlet tube 35 communicates with the housing 33, this tube beingconnected to a suitable conduit 36 preferably leading to a windshielddefroster, although said conduit may, of course, be directed whereverdesired. A manually controlled damper 3'! may be provided.

Secured to the U-shaped bracket It, as by welding or the like, is a.plate 38, which seats snugly against the rear edge of the casing Ill.The plate may be secured to the casing ID as by means of screws ll orother suitable means and is provided with an annular flange 43 defininga circular opening which substantially conforms to the path of fanblades 30.

The heating unit [2 may be of any standard or other suitable type and,in the embodiment shown, comprises headers 45, 45, saidrhe'aders beingconnected by tubular elements 46, heat exchange fins being carried bysaid tubes. A sheet of foraminous material 48 may be secured to thefront of the heating unit for filtering out any trash or the like whichmay be drawn into the current of air. 7

The casing l0 comprises a shell having a substantially circular wall 53,except for the lower portion where the walls extend downwardly to form asubstantially rectangular portion with a bottom wall 40, side walls 52,and a front wall 53. A front flange 54 is formed integrally withv theapproximately circular portion 50. Louvers or vents 55 may be formed inthe walls 52-53, said vents extending around the corners so as to permitair to be directed forwardly and laterally. Reference to Figs. 9 and 10will show that the wall of the casing is deformed adjacent the vents 55,as indicated at 55', in order to provide outwardly and downwardlyextending passages whereby warm air may be permanently directed toward apersons feet.

Studs S projecting inwardly from the front wall of the casing, andpreferably having resilient jackets S thereon, serve as bumpers or stopsfor the heating unit.

A plurality of bosses 51 are formed on the inside of the front wall 53and flange 54, to which are secured as by screws or the like, springclips 58, which serve to retain a ring 59. Preferably one clip 58 isattached to the wall 53 while two of said clips are connected to thecircular flange 54, these clips being preferably equally spaced. Helicalsprings 56 may be seated against the clips 58 and coiled around theretaining screws, as seen best in Fig. 8, in connection with some or allof the clips. The ring 59 is provided with an annular shoulder Bil, asseen best in Fig. 2, whereby it seats snugly and rotatably against aninwardly extending annular flange Bl formed on the front flange 54, saidannular flange 6i continuing along the entire circumference to serve asa bearing against ring 59.

Preferably integral with the ring 59 is a radially slotted front segment63 which, when viewed from the front, as in Figs. 1, 3, and 5, occupiessubstantially a semi-circle. When viewed in radial section, as in Fig.2, the segment 63 is arcuate in form, and it will be seen that itscurvature approximates that of a quadrant of an ellipse viewed along itsmajor axis.

The radial elements of the segmental member 63 radiate from an annularmember 64 from which extends inwardly a hollow substantially conicalelement 55, said conical element being slotted in its upper portion forabout half of its periphery, as at 66.

A valve plate 68 of a contour conforming with that of the segmentalelement 63 is rotatably mounted on the inside thereof, being retained bya shoulder formed in a ring 69, which ring may be riveted or otherwisesecured to the shoulder Bil of the segmental element. The plate 68 (Fig.6) is provided with radial slots 10 conforming substantially with theslots of the segmental element 63, and a manipulating member H issecured to the upper portion of said plate, this manipulating memberhaving a neck i2 extending through a slot '13 in the segmental member53, whereby the plate 58 may be rotated the space of one slot so as toopen or close the segmental member to the passage of air.

A pair of quadrant shaped doors 75, E5, is rotatably mounted oppositethe segmental member 63, being retained by means of a groove 13 in thering 59. These doors 15 (Fig. 7), each of which has a manipulatingmember 15 hereon, are substantially similar in radial section to thecurvature of the segmental member 63 and the apertured plate 68 mountedtherebehind. The doors 15 are mounted to be slidable behind theapertured plate 63 and may be rotated individually so as to open eitherone quadrant or both quadrants in the front of the casing Ill. Theapertured plate 68, of course, may be moved to open or close the slotsin the segmental member 63 independently of the doors [5. It should alsobe noted that the segmental member 63 along with the plate 68 and doors'15 may be rotated as a unit, these parts providing a substantiallyspheroidal surface.

Attached to the inside of the conical member 65, and substantiallyconforming to the contour thereof, is a hollow conical valve member 18,the latter being retained as .by means of a bolt 19 or the like passingthrough the bases of both cones. The peripheral portion of the conicalelement 78 is curved outwardly bell like to form a circular lip whichseats against an annular shoulder 80 formed on the inside of the annularmember 64. The conical valve 18 is slotted to conform to the slots 86 ofthe conical portion 65 and is provided with an outwardly extendingcup-shaped portion 8| which serves as a handle, whereby the valve 13 maybe rotated with reference to the conical portion 55 so as to open orclose the slots 66. The annular member 64 is also provided with ashoulder 84 on the outer periphery thereof for seating the valve plate68. A ring 85 is secured as by riveting or the like to the conicalportion 65 and has a peripheral groove 8'! formed therein for slidablyseating the quadrant shaped doors 15.

In operation, the performance of the device will vary according to thepositioning of the various valves and doors. Considering first asituation as illustrated in Fig. 9, wherein the valve plate 68 ispositioned to close the radial apertures of the segmental member 63, thequadrant shaped doors 15 are closed, and the conical valve member 18 ispositioned to close the vents 66, it will be seen that all the airprojected forwardly by the fan 30 will pass through the heating unitand, except for a small portion of heated air which will escape at thebottom of the casing through the louvers 55, substantially all of theair, upon coming in contact with the closed front of the casing, will bedrawn back by the centrifugal blower 25 and caused to retrace itspassage through the heating unit and then .blown out through the conduit35 to a defroster or wherever else it may be directed.

Considering next a condition as illustrated in Fig. 2, wherein one orboth of the quadrant shaped doors [5 is or are closed while the vents inthe segmental member 63 are closed and the valve 78 is positioned towholly or partially open the vents 6B in the conical element 65, it willbe seen that a substantial portion of the air which is projectedforwardly through the heat exchange unit is drawn back by thecentrifugal blower, thus being reheated before it is blown out by theblower through the conduit 35. However, in this case this air which isdrawn back by the centrifugal blower is diluted by cooler air drawn inthrough the vents 6B and which is heated by only a'single passagethrough the heat exchange unit. Thus it will be seen that the valve 18may be adjusted to this position when a lower temperature of air fordefrosting or other purposes is desired than in the case of Fig. 9.

In the adjustment illustrated in Figs. 1 and 10, the segmental element63 is still closed but the doors 15 are open. In this case a substantialportion of air which is directed forwardly by the fan 30 is blown outthrough the substantially semi-circular opening in the lower portion ofthe front of the casing as shown by the arrows. This illustrates theadvantages as to eificiency obtained by the curved front of the casing.Instead of the air being directed straight forwardly through the heatingunit and thence directly and difiusedly out into the space to be heated,as in the ordinary heater of this type, there is pro- .jected a largeproportion of heated air around opposite sides of central cone andthence downwardly against the curved surface defined by the segmentalmember 63. A greater concentration of warm air is thus provided atpoints adjacent the heater, so that the air is less diffused, andespecially at points adjacent the floorboard, than in devices where itis projected directly forwardly of the heater. Thus, the more or lesselliptical surface of the segmental element serves to direct downwardlyor in any other direction in which the segmental member may be turned, aconcentrated envelope of warm air rather than a diffused stream. It willbe understood that either one of the doors may be partially or whollyclosed, thu further concentrating the ejected air stream.

Of course, in the arrangement of Figs. 1 and the vents 65 in the conicalvalve may or may not be opened as desired, depending upon whether or notone wishes to dilute the air which is being drawn back by thecentrifugal blower. In either event, of course, a substantial portion ofair will be so drawn back for ejection through the outlet 35.

Numerous other combinations of adjustments may be made.

It will be understood that, under all circumstances, at least part ofthe air which is ejected by the centrifugal blower will have been twiceheated by reason of its having been first blown forwardly through theheat exchange unit and thereafter drawn backwardly therethrough by thecentrifugal blower. Also, under all circumstances, a certain amount ofheated air will be blown out and downwardly through the permanently openvents 55.

As an indication of the superior efficiency of our improved heater, itmay be noted that the outlet area provided when the lower doors 15,

are open is substantially equal to the cross sectional area of the heatexchange element. This is a great improvement over heaters of the typepreviously known, considering that, in addition, the current of air isgiven the optimum direction of flow and heat concentration.

Various changes coming within the scope of our invention may suggestthemselves to those skilled in the art, and, hence, we do not wish to berestricted to the specific form shown or uses mentioned, except to theextent indicated in the appended claims, which are to be interpreted asbroadly as the state of the art will permit.

The word laterally is used in the claims to mean a direction away fromthe axis of the blower or fan.

We claim:

1. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air therethrough, and a casingenclosing said unit, said casing comprising an outwardly curved membersubstantially closing the front thereof, a portion of said member havingvents with means for optionally opening or closing said vents, and meansfor adjustably opening the remaining portion of the front closuremember.

2. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air forwardly therethrough, and acasing enclosing said unit, said casing comprising an outwardly curvedfront closure element, a portion of said element having vents with meansfor optionally opening or closing said vents, and

means for partially or wholly opening the remaining portion of saidelement, said element having a vent adjacent the central portion thereofwith means for optionally opening or closing the same, and means fordrawing air rearwardly through said central vent and rearwardly throughsaid unit.

closure portion is adjustable and unvented for alternatively closing oropening that portion of the casing front not covered by said aperturedsegment.

4. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air therethrough, and a casingenclosing said unit, said casing comprising an outwardly curved frontportion, said front portion including a member having a spheroidalsurface, and adjustable means for providing an opening in said surface,said front portion being rotatable as a whole about an axis parallel tothe direction of air flow through said casing and said adjustable meansbeing also operable independently for variably venting said member.

5. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air therethrough, and a casingenclosing said unit and having a circular air discharge opening therein,outwardly curved vented closure means occupying less than 360 of saidopening, and adjustable unvented closure means occupying the remainderof said opening for alternatively closing or opening that portion of thecasing front not covered by said vented closure 'means, said adjustableclosure means being curved to conform with said first mentioned closuremeans, whereby it may be rotated into nested relation therewith aboutthe axis of said opening.

6. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air therethrough, and a casingenclosing said unit and having a circular air discharge opening therein,outwardly curved closure means occupying less than 360 of said opening,means for adjustably venting the first mentioned closure means, andadjustable closure means 00- cupying the remainder of said opening, saidadjustable closure means being curved to conform with first mentionedclosure means whereby it may be rotated into nested relation therewithabout the axis of said opening.

'7, A heater of the class described, comprising a heat exchange unit,means for projecting a current of air forwardly therethrough, means forinducing a current of air to flow rearwardly therethrough, and a casingenclosing said unit, the front portion of said casing having a centralclosure element therein, means for adjustably opening the front portionof said casing latducing a current of air to flow rearwardlytherethrough, and a casing enclosing said unit, the front portion ofsaid casing having an inwardly concave cup shaped element adjacentthecentral portion thereof, means for optionally and adjustably openingthe front portion of said casing laterally of said element, and meansfor adjustably venting said element, whereby the air drawn rearwardlythrough said heat exchange unit .may be diluted with outside air.

9. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air forwardly therethrough, means forinducing a current of air to flow rearwardly therethrough, and a casingenclosing said unit, said casing having a substantially circular openingin the front portion thereof, means rotatably mounted in said circularopening to form a closure therefor, said closure means having aninwardly concave, cup shaped member adjacent the central portionthereof, means adjustably venting said cup shaped member, and meansadjustably venting said front closure laterally of said cup shapedmember.

10. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air forwardly therethrough, means forinducing a current of air to flow rearwardly therethrough, and a casingenclosing said unit, said casing having a substantially circular openingin the front portion thereof, means rotatably mounted in said circularopening to form a closure therefor, said closure means having aninwardly concave, cup shaped ventable member adjacent the centralportion thereof, said closure member outwardly of said cup shaped memberbeing spheroidal in radial section, and means adjustably venting thelatter.

11. A heater of the class described, comprising a heat exchange unit,means for projecting a ourrent of air forwardly therethrough, a casingenclosing said unit, the front portion of said casing having a circularair discharge opening therein, a closure element mounted to rotate as aunit in said opening on an axis transverse to the plane of said opening,said closure element including a segmental portion occupying only a partof said opening and having variable venting means associated therewith,and adjustable closure means for the remainder of said opening andadapted to be rotated about the axis of said opening into nestedrelation with said segmental portion.

12. A heater of the class described, comprising a heat exchange unit,means for projecting a, current of air forwardly therethrough, means forinducing a current of air to flow rearwardly therethrough, a casingenclosing said unit, the front portion of said casing having a circularopening therein, a closure element mounted to rotate as a unit in saidopening, said closure element including a segmental portion andadjustable closure means occupying the remainder of said opening andadapted to be rotated into nested relation with said segmental portion,and adjustably veritable means obstructing the central portion of saidclosure element.

13. A heater of the class described, comprising a heat exchange unit,means for projecting a current of air therethrough, and a casingenclosing said unit, said casing having a substantially circular frontopening, a substantially spheroidal closure plate coverin approximatelyone-half of said opening, means for adjustably closing the remainder ofsaid opening and rotatable about an axis perpendicular to. the face ofsaid opening, and means for adjustably venting said closure plate.

ARNOLD P. HULTGREN. WALTER G. MITCHELL

